I am looking for a plugin for WooCommerce, but I can not seem to find one that has the exact feature I need. I am curious if you are able to modify it, or create a new plugin with the feature that I need, and how much it will cost. I need to be able to limit quantity of one product, based on the quantity of another product in the cart already. For example:
customer places product “A” in the cart, and then is allowed to place up to “X” number of product “B” into the cart.
So if 1 of product “A” is in the cart, and I have set “X” to 2 for the quantity of “B” in the admin panel, then the customer can then be allowed to place and purchase up to 2 of product “B”. If 2 of product “A” is in the cart, then up to 4 of product “B” can be placed in the cart and purchased, and so on.
Hopefully you can point me in the direction of one of your existing plugins that can do this, or modify one of your existing ones, or even create a new one. Thank you and I hope to hear from anyone soon.
Also, I would like this plugin to be a one time purchase, not a monthly fee, or if there is a free plugin option that I just missed, even better.

I have searched with as many keywords as I can think of, and looked through all the plugins I could find. None of the documentations and screen shots or free plugin versions I tried, had the ability to do what I need. I have posted on the WooCommerce section of Reddit, and gotten only one response with a suggestion for a plugin I already looked at and that was a monthly/yearly fee. Now I am contacting here, and to several plugin support pages asking for anyone to point me to an existing plugin that I missed, or modify an existing plugin they have, or create a new one.